Rein CPE0039 Engine Coolant Reservoir Cap - Right
OE Quality 60-Day Returns
Rein

Rein CPE0039 Engine Coolant Reservoir Cap - Right

Brand Rein CPE0039
Application Type ApplicationSpecific
Color Black
Container Type BG
Country of Origin DE
Item Height 0.7500
Item Length 3.5000
Item Level GTIN 888544080333
Item Qty 1
Item UOM EA
Item Weight 0.1400
Item Weight Unit UOM LB
Item Width 3.5000
Link to Manufacturer Page www.reinautomotive.com
Product Desc Extended 240 Rein OE Quality expansion tank caps are designed to be direct replacements for OE caps. Rein caps are designed to match or exceed the OE materials used and are produced to the highest standards to ensure long service life.
Product Desc Invoice 40 Rein Expansion Tank Cap
Product Desc Long 80 Rein OE Quality Expansion Tank Cap
Product Desc Short 20 Expansion Tank Cap
Warranty Distance 24000
Fits Audi and Volkswagen · 272 vehicles

OE direct replacement. Direct fit for the coolant reservoir cap.

OE-quality materials. Matches or exceeds OE materials for long service life.

Pressure-spec cap. Meets OE pressure requirements to keep the cooling system sealed.

Cross-references 2Q0121321, 2Q0121321A and 3C0121321 for the same application. See all 4.

$22.87Free shipping
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Free shipping to the continental U.S.
Free returns within 60 days if it doesn't fit when fitment is verified.
Not what you need? See all Engine Coolant Reservoir Cap options

OE-Quality Expansion Tank Cap

Rein CPE0039 is an OE-quality engine coolant reservoir cap built as a direct replacement for the factory cap. It is engineered to maintain the cooling system pressure specified by the vehicle manufacturer, helping preserve proper coolant system operation on Audi and Volkswagen applications.

Designed for fitment across a wide range of VW and Audi models, this expansion tank cap is a practical replacement for worn, cracked, or pressure-weak caps. The Rein CPE0039 is produced to match or exceed OE material standards and tolerances for consistent sealing performance.

Key Features

  • Manufactured to strict engineering standards for materials and tolerances
  • Direct-fit replacement for the original expansion tank cap
  • Meets or exceeds OE pressure specifications
  • Produced by an original equipment supplier
  • Black finish

Detailed Description

The Rein OE Quality expansion tank cap is designed for drivers and technicians who need a dependable coolant reservoir cap replacement without changing the factory cooling system design. Part number CPE0039 is made to support proper pressure retention in the expansion tank, which is critical for stable coolant system performance. It is a strong match for many Audi A3, S3, Q3, TT, and Volkswagen Golf, GTI, Tiguan, Atlas, and Jetta applications, among others.

This part cross-references 2Q0121321 and 3C0121321 for the same application.

What It Helps Fix

  • Coolant loss from a cap that no longer seals correctly
  • Pressure-related cooling system faults caused by a weak reservoir cap
  • Cracked, worn, or damaged expansion tank cap components
  • Improper coolant system pressure on Audi and Volkswagen vehicles
  • Service issues tied to an aging OE coolant reservoir cap

Installation Notes and Tips

Install CPE0039 on the correct expansion tank application and verify the cap style matches the vehicle’s OE design. Confirm the cap seats fully and locks in place before returning the vehicle to service. For fitment-specific applications, use the vehicle’s year, make, model, and position details to confirm compatibility, including Audi Q5 PHEV right-side and Audi A7 Sportback right-side listings.

Compatible With 2015-2020 Audi A3 Quattro, 2022-2026 Audi A3 Quattro, 2015-2020 Audi S3, 2022-2026 Audi S3, 2015-2025 Audi Q3, 2022-2025 Audi Q4 e-tron, 2022-2025 Audi Q4 e-tron Sportback, 2020-2025 Audi Q5 PHEV right, 2022-2025 Audi RS3, 2017-2020 Audi RS3, 2018-2025 Volkswagen Atlas, 2020-2025 Volkswagen Atlas Cross Sport, 2022-2025 Volkswagen Golf R, 2015-2019 Volkswagen Golf R, 2015-2025 Volkswagen GTI, 2025 Volkswagen ID. Buzz, 2021-2025 Volkswagen ID.4, 2017-2025 Volkswagen Jetta, 2022-2025 Volkswagen Taos, 2009-2025 Volkswagen Tiguan, 2022-2024 Audi A3, 2015-2020 Audi A3, 2016-2023 Audi TT Quattro, 2016-2023 Audi TTS Quattro, 2019-2023 Volkswagen Arteon, 2021-2022 Audi A7 Sportback right, 2018-2022 Audi TT RS Quattro, 2018-2022 Volkswagen Passat, 2015 Volkswagen Passat, 2006-2010 Volkswagen Passat, 2020-2021 Audi A8 Quattro auxiliary, 2015-2021 Volkswagen Golf, 2015-2020 Volkswagen e-Golf, 2018-2019 Volkswagen Beetle, 2017-2019 Volkswagen Golf Alltrack, 2015-2019 Volkswagen Golf SportWagen, 2016-2018 Audi A3 Sportback e-tron, 2011-2018 Audi A8 Quattro, 2015-2018 Audi Q3 Quattro, 2013-2018 Audi S8, 2018 Audi TT, 2016 Audi TT, 2017-2018 Volkswagen Tiguan Limited, 2017 Volkswagen Beetle, 2009-2017 Volkswagen CC, 2008-2010 Audi TT w/Black Cap, 2009-2010 Audi TT Quattro w/Black Cap, 2009-2010 Audi TTS Quattro w/Black Cap, 2010 Volkswagen Golf City w/Black Cap, 2009-2010 Volkswagen Passat CC, and 2009 Volkswagen Golf City w/Black Cap.

Quality Assurance

Rein designs this expansion tank cap as an OE-quality replacement produced to original equipment standards. Part number CPE0039 is backed by a 24,000-mile warranty.

This part fits 272 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelSubmodelLitersCylindersFuel TypePositionNotes
2026AudiA3 Quattro—2.0LL4—N/A—
2026AudiS3—2.0LL4—N/A—
2025AudiA3 Quattro—2.0LL4—N/A—
2025AudiQ3—2.0LL4—N/A—
2025AudiQ4 e-tron—-L--BATTERY EV (EV/BEV)N/A—
2025AudiQ4 e-tron Sportback—-L--BATTERY EV (EV/BEV)N/A—
2025AudiQ5 PHEV—2.0LL4—Right—
2025AudiRS3—2.5LL5—N/A—
2025AudiS3—2.0LL4—N/A—
2025VolkswagenAtlas—2.0LL4—N/A—
2025VolkswagenAtlas Cross Sport—2.0LL4—N/A—
2025VolkswagenGolf R—2.0LL4—N/A—
2025VolkswagenGTI—2.0LL4—N/A—
2025VolkswagenID. Buzz—-L--BATTERY EV (EV/BEV)N/A—
2025VolkswagenID.4—-L--BATTERY EV (EV/BEV)N/A—
2025VolkswagenJetta—1.5LL4—N/A—
2025VolkswagenTaos—1.5LL4—N/A—
2025VolkswagenTiguan—2.0LL4—N/A—
2024AudiA3—2.0LL4—N/A—
2024AudiA3 Quattro—2.0LL4—N/A—
2024AudiQ3—2.0LL4—N/A—
2024AudiQ4 e-tron—-L--BATTERY EV (EV/BEV)N/A—
2024AudiQ4 e-tron Sportback—-L--BATTERY EV (EV/BEV)N/A—
2024AudiQ5 PHEV—2.0LL4—Right—
2024AudiRS3—2.5LL5—N/A—
2024AudiS3—2.0LL4—N/A—
2024VolkswagenAtlas—2.0LL4—N/A—
2024VolkswagenAtlas Cross Sport—2.0LL4—N/A—
2024VolkswagenGolf R—2.0LL4—N/A—
2024VolkswagenGTI—2.0LL4—N/A—
2024VolkswagenID.4—-L--BATTERY EV (EV/BEV)N/A—
2024VolkswagenJetta—1.5LL4—N/A—
2024VolkswagenTaos—1.5LL4—N/A—
2024VolkswagenTiguan—2.0LL4—N/A—
2023AudiA3—2.0LL4—N/A—
2023AudiA3 Quattro—2.0LL4—N/A—
2023AudiQ3—2.0LL4—N/A—
2023AudiQ4 e-tron—-L--BATTERY EV (EV/BEV)N/A—
2023AudiQ4 e-tron Sportback—-L--BATTERY EV (EV/BEV)N/A—
2023AudiQ5 PHEV—2.0LL4—Right—
2023AudiRS3—2.5LL5—N/A—
2023AudiS3—2.0LL4—N/A—
2023AudiTT Quattro—2.0LL4—N/A—
2023AudiTTS Quattro—2.0LL4—N/A—
2023VolkswagenArteon—2.0LL4—N/A—
2023VolkswagenAtlas—2.0LL4—N/A—
2023VolkswagenAtlas Cross Sport—2.0LL4—N/A—
2023VolkswagenGolf R—2.0LL4—N/A—
2023VolkswagenGTI—2.0LL4—N/A—
2023VolkswagenID.4—-L--BATTERY EV (EV/BEV)N/A—
2023VolkswagenJetta—1.5LL4—N/A—
2023VolkswagenTaos—1.5LL4—N/A—
2023VolkswagenTiguan—2.0LL4—N/A—
2022AudiA3—2.0LL4—N/A—
2022AudiA3 Quattro—2.0LL4—N/A—
2022AudiA7 Sportback—2.0LL4—Right—
2022AudiQ3—2.0LL4—N/A—
2022AudiQ4 e-tron—-L--BATTERY EV (EV/BEV)N/A—
2022AudiQ4 e-tron Sportback—-L--BATTERY EV (EV/BEV)N/A—
2022AudiQ5 PHEV—2.0LL4—Right—
2022AudiRS3—2.5LL5—N/A—
2022AudiS3—2.0LL4—N/A—
2022AudiTT Quattro—2.0LL4—N/A—
2022AudiTT RS Quattro—2.5LL5—N/A—
2022AudiTTS Quattro—2.0LL4—N/A—
2022VolkswagenArteon—2.0LL4—N/A—
2022VolkswagenAtlas—2.0LL4—N/A—
2022VolkswagenAtlas—3.6LV6—N/A—
2022VolkswagenAtlas Cross Sport—2.0LL4—N/A—
2022VolkswagenAtlas Cross Sport—3.6LV6—N/A—
2022VolkswagenGolf R—2.0LL4—N/A—
2022VolkswagenGTI—2.0LL4—N/A—
2022VolkswagenID.4—-L--ELECTRICN/A—
2022VolkswagenJetta—1.5LL4—N/A—
2022VolkswagenPassat—2.0LL4—N/A—
2022VolkswagenTaos—1.5LL4—N/A—
2022VolkswagenTiguan—2.0LL4—N/A—
2021AudiA7 Sportback—2.0LL4—Right—
2021AudiA8 QuattroL Plug-In Hybrid3.0LV6—Auxiliary—
2021AudiQ3—2.0LL4—N/A—
2021AudiQ5 PHEV—2.0LL4—Right—
2021AudiTT Quattro—2.0LL4—N/A—
2021AudiTT RS Quattro—2.5LL5—N/A—
2021AudiTTS Quattro—2.0LL4—N/A—
2021VolkswagenArteon—2.0LL4—N/A—
2021VolkswagenAtlas—2.0LL4—N/A—
2021VolkswagenAtlas—3.6LV6—N/A—
2021VolkswagenAtlas Cross Sport—2.0LL4—N/A—
2021VolkswagenAtlas Cross Sport—3.6LV6—N/A—
2021VolkswagenGolf—1.4LL4—N/A—
2021VolkswagenGTI—2.0LL4—N/A—
2021VolkswagenID.4—-L--ELECTRICN/A—
2021VolkswagenJetta—1.4LL4—N/A—
2021VolkswagenJetta—2.0LL4—N/A—
2021VolkswagenPassat—2.0LL4—N/A—
2021VolkswagenTiguan—2.0LL4—N/A—
2020AudiA3—2.0LL4—N/A—
2020AudiA3 Quattro—2.0LL4—N/A—
2020AudiA8 QuattroL Plug-In Hybrid3.0LV6—Auxiliary—
2020AudiQ3—2.0LL4—N/A—
2020AudiQ5 PHEV—2.0LL4—Right—
2020AudiRS3—2.5LL5—N/A—
2020AudiS3—2.0LL4—N/A—
2020AudiTT Quattro—2.0LL4—N/A—
2020AudiTT RS Quattro—2.5LL5—N/A—
2020AudiTTS Quattro—2.0LL4—N/A—
2020VolkswagenArteon—2.0LL4—N/A—
2020VolkswagenAtlas—2.0LL4—N/A—
2020VolkswagenAtlas—3.6LV6—N/A—
2020VolkswagenAtlas Cross Sport—2.0LL4—N/A—
2020VolkswagenAtlas Cross Sport—3.6LV6—N/A—
2020Volkswagene-Golf—-L--—N/A—
2020VolkswagenGolf—1.4LL4—N/A—
2020VolkswagenGTI—2.0LL4—N/A—
2020VolkswagenJetta—1.4LL4—N/A—
2020VolkswagenJetta—2.0LL4—N/A—
2020VolkswagenPassat—2.0LL4—N/A—
2020VolkswagenTiguan—2.0LL4—N/A—
2019AudiA3—2.0LL4—N/A—
2019AudiA3 Quattro—2.0LL4—N/A—
2019AudiQ3—2.0LL4—N/A—
2019AudiRS3—2.5LL5—N/A—
2019AudiS3—2.0LL4—N/A—
2019AudiTT Quattro—2.0LL4—N/A—
2019AudiTT RS Quattro—2.5LL5—N/A—
2019AudiTTS Quattro—2.0LL4—N/A—
2019VolkswagenArteon—2.0LL4—N/A—
2019VolkswagenAtlas—2.0LL4—N/A—
2019VolkswagenAtlas—3.6LV6—N/A—
2019VolkswagenBeetle—2.0LL4—N/A—
2019Volkswagene-Golf—-L--ELECTRICN/A—
2019VolkswagenGolf—1.4LL4—N/A—
2019VolkswagenGolf Alltrack—1.8LL4—N/A—
2019VolkswagenGolf R—2.0LL4—N/A—
2019VolkswagenGolf SportWagen—1.4LL4—N/A—
2019VolkswagenGolf SportWagen—1.8LL4—N/A—
2019VolkswagenGTI—2.0LL4—N/A—
2019VolkswagenJetta—1.4LL4—N/A—
2019VolkswagenJetta—2.0LL4—N/A—
2019VolkswagenPassat—2.0LL4—N/A—
2019VolkswagenTiguan—2.0LL4—N/A—
2018AudiA3—2.0LL4—N/A—
2018AudiA3 Quattro—2.0LL4—N/A—
2018AudiA3 Sportback e-tron—1.4LL4—N/A—
2018AudiA8 Quattro—3.0LV6—N/A—
2018AudiA8 Quattro—4.0LV8—N/A—
2018AudiQ3—2.0LL4—N/A—
2018AudiQ3 Quattro—2.0LL4—N/A—
2018AudiRS3—2.5LL5—N/A—
2018AudiS3—2.0LL4—N/A—
2018AudiS8—4.0LV8—N/A—
2018AudiTT—1.8LL4—N/A—
2018AudiTT Quattro—2.0LL4—N/A—
2018AudiTT RS Quattro—2.5LL5—N/A—
2018AudiTTS Quattro—2.0LL4—N/A—
2018VolkswagenAtlas—2.0LL4—N/A—
2018VolkswagenAtlas—3.6LV6—N/A—
2018VolkswagenBeetle—2.0LL4—N/A—
2018Volkswagene-Golf—-L--ELECTRICN/A—
2018VolkswagenGolf—1.8LL4—N/A—
2018VolkswagenGolf Alltrack—1.8LL4—N/A—
2018VolkswagenGolf R—2.0LL4—N/A—
2018VolkswagenGolf SportWagen—1.8LL4—N/A—
2018VolkswagenGTI—2.0LL4—N/A—
2018VolkswagenJetta—1.8LL4—N/A—
2018VolkswagenPassat—2.0LL4—N/A—
2018VolkswagenTiguan—2.0LL4—N/A—
2018VolkswagenTiguan Limited—2.0LL4—N/A—
2017AudiA3—2.0LL4—N/A—
2017AudiA3 Quattro—2.0LL4—N/A—
2017AudiA3 Sportback e-tron—1.4LL4—N/A—
2017AudiA8 Quattro—3.0LV6—N/A—
2017AudiA8 Quattro—4.0LV8—N/A—
2017AudiQ3—2.0LL4—N/A—
2017AudiQ3 Quattro—2.0LL4GASN/A—
2017AudiRS3—2.5LL5—N/A—
2017AudiS3—2.0LL4—N/A—
2017AudiS8—4.0LV8—N/A—
2017AudiTT Quattro—2.0LL4—N/A—
2017AudiTTS Quattro—2.0LL4—N/A—
2017VolkswagenBeetle—1.8LL4—N/AFrom 6/1/17
2017VolkswagenBeetle—2.0LL4—N/AFrom 6/1/17
2017VolkswagenCC—3.6LV6—N/A—
2017Volkswagene-Golf—-L--ELECTRICN/A—
2017VolkswagenGolf—1.8LL4—N/A—
2017VolkswagenGolf Alltrack—1.8LL4—N/A—
2017VolkswagenGolf R—2.0LL4—N/A—
2017VolkswagenGolf SportWagen—1.8LL4—N/A—
2017VolkswagenGTI—2.0LL4—N/A—
2017VolkswagenJetta—1.8LL4—N/A—
2017VolkswagenTiguan—2.0LL4—N/A—
2017VolkswagenTiguan Limited—2.0LL4—N/A—
2016AudiA3—1.8LL4—N/A—
2016AudiA3—2.0LL4DIESELN/A—
2016AudiA3 Quattro—2.0LL4—N/A—
2016AudiA3 Sportback e-tron—1.4LL4—N/A—
2016AudiA8 Quattro—3.0LV6GASN/A—
2016AudiA8 Quattro—4.0LV8—N/A—
2016AudiA8 Quattro—6.3LW12—N/A—
2016AudiQ3—2.0LL4GASN/A—
2016AudiQ3 Quattro—2.0LL4—N/A—
2016AudiS3—2.0LL4—N/A—
2016AudiS8—4.0LV8—N/A—
2016AudiTT—2.0LL4—N/A—
2016AudiTT Quattro—2.0LL4—N/A—
2016AudiTTS Quattro—2.0LL4—N/A—
2016VolkswagenCC—3.6LV6—N/A—
2016Volkswagene-Golf—-L--ELECTRICN/A—
2016VolkswagenGolf—1.8LL4—N/A—
2016VolkswagenGolf R—2.0LL4—N/A—
2016VolkswagenGolf SportWagen—1.8LL4—N/A—
2016VolkswagenGTI—2.0LL4—N/A—
2016VolkswagenTiguan—2.0LL4—N/A—
2015AudiA3—1.8LL4—N/A—
2015AudiA3—2.0LL4DIESELN/A—
2015AudiA3 Quattro—2.0LL4—N/A—
2015AudiA8 Quattro—3.0LV6GASN/A—
2015AudiA8 Quattro—4.0LV8—N/A—
2015AudiA8 Quattro—6.3LW12—N/A—
2015AudiQ3—2.0LL4GASN/A—
2015AudiQ3 Quattro—2.0LL4—N/A—
2015AudiS3—2.0LL4—N/A—
2015AudiS8—4.0LV8—N/A—
2015VolkswagenCC—3.6LV6—N/A—
2015Volkswagene-Golf—-L--ELECTRICN/A—
2015VolkswagenGolf—1.8LL4—N/A—
2015VolkswagenGolf—2.0LL4DIESELN/A—
2015VolkswagenGolf R—2.0LL4—N/A—
2015VolkswagenGolf SportWagen—1.8LL4—N/A—
2015VolkswagenGolf SportWagen—2.0LL4DIESELN/A—
2015VolkswagenGTI—2.0LL4—N/A—
2015VolkswagenPassat—2.0LL4DIESELN/A—
2015VolkswagenTiguan—2.0LL4—N/A—
2014AudiA8 Quattro—3.0LV6GASN/A—
2014AudiA8 Quattro—4.0LV8—N/A—
2014AudiA8 Quattro—6.3LW12—N/A—
2014AudiS8—4.0LV8—N/A—
2014VolkswagenCC—3.6LV6—N/A—
2014VolkswagenTiguan—2.0LL4—N/A—
2013AudiA8 Quattro—3.0LV6—N/A—
2013AudiA8 Quattro—4.0LV8—N/A—
2013AudiA8 Quattro—6.3LW12—N/A—
2013AudiS8—4.0LV8—N/A—
2013VolkswagenCC—3.6LV6—N/A—
2013VolkswagenTiguan—2.0LL4—N/A—
2012AudiA8 Quattro—4.2LV8—N/A—
2012AudiA8 Quattro—6.3LW12—N/A—
2012VolkswagenCC—3.6LV6—N/A—
2012VolkswagenTiguan—2.0LL4—N/A—
2011AudiA8 Quattro—4.2LV8—N/A—
2011VolkswagenCC—3.6LV6—N/A—
2011VolkswagenTiguan—2.0LL4—N/A—
2010AudiTT—2.0LL4—N/Aw/Black Cap
2010AudiTT Quattro—2.0LL4—N/Aw/Black Cap
2010AudiTTS Quattro—2.0LL4—N/Aw/Black Cap
2010VolkswagenCC—3.6LV6—N/A—
2010VolkswagenGolf City—2.0LL4—N/Aw/Black Cap
2010VolkswagenPassat—3.6LV6—N/A—
2010VolkswagenPassat CC—3.6LV6—N/A—
2010VolkswagenTiguan—2.0LL4—N/A—
2009AudiTT—2.0LL4—N/Aw/Black Cap
2009AudiTT Quattro—2.0LL4—N/Aw/Black Cap
2009AudiTTS Quattro—2.0LL4—N/Aw/Black Cap
2009VolkswagenCC—3.6LV6—N/A—
2009VolkswagenGolf City—2.0LL4—N/AFrom 4/13/09, w/Black Cap
2009VolkswagenPassat—3.6LV6—N/A—
2009VolkswagenPassat CC—3.6LV6—N/A—
2009VolkswagenTiguan—2.0LL4—N/A—
2008AudiTT—2.0LL4—N/Aw/Black Cap
2008VolkswagenPassat—3.6LV6—N/A—
2007VolkswagenPassat—3.6LV6—N/A—
2006VolkswagenPassat—3.6LV6—N/A—
Directly replaces or cross-references 4 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
2Q01213212Q0121321A3C01213215Q0121321